Data Center Alley

AWS · Equinix · Digital Realty · QTS · CloudHQ · Ashburn / Sterling, Virginia

Water — consumed, not returned

Taken from the basin10,419M gal/yr
Evaporated on site1,699M gal
Making the power8,720M gal
Basin stressMedium-High
Where the water comes from
Municipal potable supply
Cooling
Mixed — legacy evaporative towers alongside newer closed-loop halls
Basis
Fitted to a published figure of 1,700 million gallons a year

Air — what the stacks emit

Nitrogen oxides1,917t/yr
Sulphur dioxide1,704t/yr
Fine particulates256t PM2.5
Health damages$224M/yr
Where it burns
PJM Dominion — Virginia
Generation mix
Gas 55 · Nuclear 30 · Coal 4 · Solar 5
CO₂e
6,708 kt/yr — climate, not air quality

Who wanted it

Who asked for it
Effectively everyone — us-east-1 alone underpins a large share of consumer apps, SaaS and federal cloud
Who approved it
Loudoun County created the by-right PD-OP zoning in the 1990s; Dominion Energy interconnection; Virginia's sales-tax exemption on data center equipment renewed through 2035
What it serves
AWS us-east-1, the default region of the internet; plus most major colo and peering
IT capacity
3,400 MW running of 5,200 MW announced

The densest concentration of data centers on Earth — roughly a quarter of global colocation capacity in one county. Its growth is the single largest driver of PJM's record 2025 capacity auction prices, which raised bills across thirteen states.

ratepayer-cost disputewater-stressed basin

Where it is

39.0437°, -77.4875°

Water and air figures are modelled from disclosed capacity, not measured — site-level error is roughly ±40%. Diesel backup generators are not counted, so on-site figures are floors. Full method.